5-Fluoro-2-(4-fluorophenyl)-7-methyl-3-phenylsulfinyl-1-benzofuran

In the title compound, C21H14F2O2S, the dihedral angles between the mean plane [r.m.s. deviation = 0.007 (2) Å] of the benzofuran ring system and the pendant 4-fluorophenyl and phenyl rings are 5.93 (9) and 80.23 (5)°, respectively. In the crystal, molecules are linked by weak C—H⋯O and C—H⋯π interactions, forming a three-dimensional network.

In the title compound, C 21 H 14 F 2 O 2 S, the dihedral angles between the mean plane [r.m.s. deviation = 0.007 (2) Å ] of the benzofuran ring system and the pendant 4-fluorophenyl and phenyl rings are 5.93 (9) and 80.23 (5) , respectively. In the crystal, molecules are linked by weak C-HÁ Á ÁO and C-HÁ Á Á interactions, forming a three-dimensional network.

Related literature
For background information and the crystal structures of related compounds, see: Choi et al. (2011Choi et al. ( , 2012; Seo et al.  Table 1 Hydrogen-bond geometry (Å , ).
Cg1 is the centroid of the C16-C21 phenyl ring.

Experimental
3-Chloroperoxybenzoic acid (77%, 202 mg, 0.9 mmol) was added in small portions to a stirred solution of 5-fluoro-2-(4fluorophenyl)-7-methyl-3-phenylsulfanyl-1-benzofuran (282 mg, 0.8 mmol) in dichloromethane (30 mL) at 273 K. After being stirred at room temperature for 5h, the mixture was washed with saturated sodium bicarbonate solution and the organic layer was separated, dried over magnesium sulfate, filtered and concentrated at reduced pressure. The residue was purified by column chromatography (benzene) to afford the title compound as a colorless solid [yield 54%, m.p. 466-467 K; R f = 0.42 (benzene)]. Single crystals suitable for X-ray diffraction were prepared by slow evaporation of a solution of the title compound in benzene at room temperature.

Refinement
All H atoms were positioned geometrically and refined using a riding model, with C-H = 0.95 Å for aryl and 0.98Å for methyl H atoms. U iso (H) = 1.2U eq (C) for aryl and 1.5U eq (C) for methyl H atoms. The positions of methyl hydrogens were optimized rotationally.

Computing details
(iii) x, y + 1, z; (iv) x + 1/2, -y + 3/2, z + 1/2.] where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max = 0.001 Δρ max = 0.34 e Å −3 Δρ min = −0.29 e Å −3 Special details Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > 2sigma(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.